The present invention relates to a metallic cord for rubber articles, more particularly to a cord structure capable of improving rubber penetration, flexibility and the like of the cord.
In recent years, in order to improve penetration of rubber into steel cords used to reinforce rubber articles such as pneumatic tires, there has been proposed a cord which is formed by twisting together steel filaments including filaments which are waved by a constant wave length and a constant wave height.
In such a cord, however, buckling is liable to occur on occasion and as a result the fatigue resistance and impact load resistance are decreased.
It is therefore, an object of the present invention to provide a metallic cord in which the occurrence of buckling is effectively controlled to improve the fatigue resistance and impact load resistance as well as the rubber penetration.
According to one aspect of the present invention, a metallic cord is composed of metallic filaments gathered together, the total number of the metallic filaments is in a range of from two to twelve, and the metallic filaments include at least one patterned filament which is, before gathered together, two-dimensionally waved so as to have a wave form defined by plural kinds of cycles different from each other in respect of the wave length P and/or wave height H.